Half to stanford t



(No Model.) 2 Sheets-Sheet 1'.

S. H. HEGINBOTTOM.,-

VALVE FOR AIR BRAKES.

No. 546,664. Patented-SeptQZA.1895.

INVENTOR ANDREW lGRAHAM. PMOTO-UTNO.WASHiNGwN. DC.

2 Sheets-Sheet 2. v

(No Model.)

S. H. HEGINBOTTOM. VALVE FOR AIR BRAKES No. 546,664. I Patented Sept.24, 1895.-

VI E N R 0 I T A NrTED STATES ATENT Fmcn.

SAMUEL H. HEGINBOTTOM, OF SAGINAW, MICHIGAN, ASSIGNOR OF ON E- HALF TOSTANFORD T. ORAPO, OF SAME PLACE.

VALVQE FOR Al R-BRAK'ES.

SPECIFICATION forming part of Letters Patent No. 546,664, datedSeptember 24, 1895. Application filed April 30,1894. Serial No. 509,605.(No model.)

f0 all whom it may concern.-

Be it known that I, SAMUEL H. HEGINBO'L TOM, a citizen of the UnitedStates, residing at Saginaw, E. S., in the county of Saginaw and Stateof Michigan, have invented a certain new and useful Valve forAir-Brakes; and I do declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same, referencebeing had to the accompanying drawings, and to the letters and figuresof reference marked thereon, which form a part of this specification.

My invention is an attachment to the airbrake mechanism of alocomotivewhich makes possible certain modifications of the triple-valveconstruction and mode of operation.

The attachment or improvement hereinafter described radically effectsthe working of the driver-brake and furnishes the following distinctadvantages, viz: It is an automatic detector of the stopping of the pumpor any loss of pressure which will bleed the train reservoirs, but stillnot be sharp enough to move the triple valves and set the brakes. Itpermits the reservoir of the engine-brakes to be filled almost instantlyand maintains under all circumstances the maximum effectiveness of thisbrake. It provides for an automatic action of the'driver-brakessimultaneous with the train-brakes when the engineers valve is thrown toemergency position. This makes the emergency-stop doubly effective,because of the instantaneous response of the brake on which the engineeris not accustomed to rely. It saves wear and tear of the engine, becausethe driver-brake will not be set on usualservice stops. It causes thetrain to be brought to a stop with greater smoothness and prevents theslack from running up to the engine.

This apparatus consists of what is called a driver-brake-retainingvalve, which is situated between the train-pipe and triplevalve pistonand adapted to allow the free passage of air from the train-pipe throughthe triple-valve, but to resist the backward fiow and 4' thevalve-chamber.

of the train-pipe by means of springs until the pressure from the lowerside of the triplevalve piston overcomes the springs. Operating inconjunction with this retaining-valve is my improved driver-braketriple-valve piston, in which, in order to permit the driverbrakepiston-valve reservoir to charge more quickly, I increase the number ofports around the piston and move the piston below the ports by a springwhen the reservoir is filled.

In the drawings, Figure 1 is a sectional view of the apparatus andtriple valve with improved piston and ports. Fig. 2 is a perspective ofthe retaining-valve piston. Fig. 3 is bottom view of the valve. Fig. 4is a sectional view of my improved triple-valve piston. Fig. 5 is asectional perspective showing the retaining-valve in position when thebrake is set, also showing another form of the retaining-valve piston.

A is the triple-valve casing. B is the easing containing theretaining-valve, which I place somewhere between the train-pipe and thetriple-valve piston. The channel 5 is connected to the train-pipe andconveys the air to the driver-brake-retaining piston-valve, as shown inFigs. 1 and 5. In Fig. 1 two channels 5 and 5 are shown, the channel 5being lower and nearer to the piston-ports. The channel 5' is above 5and nearer to the valve-seat. There may be two or more of these channels5' in order to afford a freer movement of the air from the triple-valvechambers.

6, 7, and 10 is a channel conducting the air tothe triple-valve casingA. B contains, also, a cylinder-chamber 4, in which is a piston D andvalve E. O is the lower or bottom cap of this cylinder and contains acentral annular hole 0', receiving a spiral spring 1, which extendsbeyond the inner edge of the cap and against the piston D, holding it toits extreme upper throw. The set-screw C in the lower end of the bottomcap, as shown in Fig. 1, extends into the annular hole 0 against thespring 1, and by it the tension of.

the spring may be regulated.

4 is the chamber containing the piston D The piston-chamher 4 is muchlarger than the valve-chamber 4, the head of the piston D closing theopening into the smaller chamber 4:.

The piston D has in its head a central annular orifice D, adapted toreceive the wing E of the valve E, which occupies the chamher 4. In thepiston D are ports D, passing from the outside into the central orifice.These ports are connected with the channel 5 when the valve is closedand conduct the air into the orifice D. In order to permit the readyflow of air to the valve E, the piston D may be provided with acircumferentialgroove D in the plane of the ports D, permitting the airto pass around the piston along the groove to all the ports. Fig. 5shows another form of the piston D. This piston does not contain thering D', and instead of a number of ports D, as shown in Fig. 2, ithasbut one port D" passing entirely through the end of the piston. It leadsto the chamber D and is directly opposite channel 5 when the brakes arenot set, thus permitting the air to pass freely from train-pipe 5,through port D, into chamber D, then around valve E into channel 6,leading to the reservoir. The backward flow from the reservoir throughchannel 6 will strike upon the head of the piston and valve and force itdownward, when a certain number of pounds pressure is obtained, thusallowing the air to pass freely around the valve, above the top of thepiston, and out through chamber 5. As many ports may be provided asdesired.

E is the valve previously mentioned, resting upon the piston-head, withits wing E in the orifice D of the piston-head, as described. Vhenresting upon the piston-head, no air can pass from the train-pipethrough the triple valve; but under even a small pressure from thetrain-pipe the valve will be opened and the air pass through and intothe channel 6, leading to the triple valve and reservoir. Vhen thereservoir is filled, the pressure being equalized, the coiled spring 2between the valve-head and the end of the chamber 1 will close thevalve, which will remain closed so long as the pressure in the channel 6equals the pressure in the channel 5. It is obvious that if the pressurein the train-pipe be increased it will again open the valve and fill thetriple-valve chamber and reservoir; but when the pressure in thetrainpipe is lowered the valve remains in its seatin fact is held thereby the pressure from the channel 6-and when the pressure from thetrain-pipe is sufficiently decreased for the pressure from the channel 6to overcome the resistance of the springl the piston D will be forceddown upon the spring, thereby opening up a free passage for the air fromthe triple-valve chamber around the valve E, through the channels 5, tothe train-pipe. In order that the backward flow from channel 6 may beimmediate when the spring 1 is depressed, I provide the channels 5,leading from the upper part of chamber 4:, so that a very slightdepression of the spring will force the piston by these channels andopen an exit for the air. It is also seen that when the pressureunderneath the piston D has been suffieiently reduced to press down thespring 1 the piston D will leave its seat, and the pressure in channel 6will then extend into the top of chamber a and press on the largersurface of the piston D, which will accelerate the movement downward,opening the passages 5, which will allow the air in channel 6 to escapeand move the triple valve and set the brake. It is obvious that thespring 1 can he made to resist the pressure of any number of poundsdesired, and that not until the pressure in the train-pipe has beenreduced below that number of pounds can the driverbrakes be set.

G is the piston of the driver-brake triple valve, having on its stem theordinary slidevalve I, moving with it and having ports and passagesgoverning ports and passages 17 and S, 9, and 11 in the casing leadingto the brakecylinder and passage 13, to the atmosphere.

18 is a port like that now in triple valves and extending a likedistance below the piston G when the air is equal on both sides of thepiston and the spring S is extended. 15 is a port or ports much largerthan 18, which when the air is equal on both sides of the piston G andspring S extended are completely covered by piston G; but when thepressure is on the under side of piston G and spring S compressed by thepiston these ports are opened, allowing a large passage for the airupward.

H is an auxiliary device loose on the pistonstem and seated against thecylinder-shoulders when the piston is up and allowing the piston to moveindependent of it for alimited distance, as when actuated by the springS, hereinafter described. 16 are ports on the edge of this auxiliarydevice II. In a recess H in the under side of the auxiliary device lland between it and the piston and bearing against each is a spring S,which separates the auxiliary device II from the piston when not underpressure. The object of placing this spring S between the auxiliarydevice 11 and the piston G is, as previously stated, to allow the pistonto rise slightly when the pressure is on the under side, and thus openthe large ports 15, through which the reservoir is almost instantlyfilled, and when the pressure is equalized to again put the piston insuch a position where the ports 15 are closed, when it will have itsusual sensitiveness to a decrease in pressure in channel 6. It is afterthe brakes on the train and the engine have been set and the engineerthrows his lever to release the brakes that the operation of thisauxiliary device becomes effective. iVhen the brakes are released, theair from the main reservoir passes at once through the retainingvalveherein described and through the large ICO ports around the triple-valvepiston and filling the auxiliary reservoir before the air has commencedto pass into the reservoirs on the balance of the train, theengine-reservoirbeing so much nearer the seat of pressure. As soon asthe engine auxiliary reservoir is filled, which actual test demonstratesto be in eight seconds, the piston is moved by the spring S below thelarge ports. The driver-brake is now effective and is the only brake onthe train that can now be used by the engineer, should emergency requireit. It is obvious that the pressure in the train-pipe will be graduallyreduced as the reservoirs on the different cars are being filled. Thisreduction would ordinarily set the driver-brake again; but theretaining-valve heretofore described prevents this by holding thepressure in the auxiliary reservoir, as heretofore described. The firstrush of air from the main reservoir will fill the locomotive auxiliaryreservoir, and should the pump give out now, as it is most liable to, ifat all, the engineer would have a brake at his command, as we have seen.As previously stated, the retaining-valve may be adjusted to resist anynumber of pounds backward pressure desired, and that not until thatnumber of pounds pressure has been reduced in the train-pipe will thedriver-brake be set, so that it is obvious that the engineer makingservice steps can hold in reserve his driver-brake; but should emergencyrequire it he can by the sudden exhaustion of the train-pipe apply allthe brakes on the train, in which event the driver-brake would operatefirst on account of its nearness to the exhaust-valve.

It is obvious that the retaining-valve mechanism and easing can be soadjusted that the engine-brake can be gradually set for service stops,instead of with full pressure on the first application, as describedherein.

Any change in the mechanismdescribed suggested by mechanical skill canbe made Without departing from the principle of my invention. ITherefore I do not confine myselfto the special form and arrangement ofparts shown and described.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. In an automatic air brake mechanism, means in the engine brakemechanism for detectingaloss of pressure in the train pipe, comprising avalve located in the brake operating mechanism on the engine and betweenthe train pipe and the engine triple valve piston chamber, with valveports opening into the train pipe connection and the triple valve pistonchamber, the valve adapted to resist a moderate reduction of pressure inthe train pipe and to discharge air into the train pipe when itsresistance has been overcome by the pressure in the piston chamber.

2. In an automatic air brake system, means located in the brakemechanism for automatically detecting leakage in the train pipecomprising an intermediate piston valve located in the passage Wayleading to the train pipe from the engine triple valve chamber andadapted to allow the passage of air to the brake operating device of theengine and to prevent the backward fiow thereof until the pressure ofthe train pipe is reduced to a certain degree, when the valve will beoperated and discharge air from the brake triple valve piston into thetrain pipe, substantially as described.

3. In an automatic air brake system, a piston valve located in themainpassage from the engine triple valve chamber to the train pipe, adaptedto allow the passage of air to the brake triple valve chamber, and toresist by means of springs the backward flow of air into such passage,substantially as described.

4. In an automatic air brake mechanism a piston held to its extremethrow by a spring and a check valve arranged in the head of the saidpiston, the said valve held to its seat by a spring, ports leading fromthe side of the piston chamber to the valve seat, all in a casinglocated intermediate of the train pipe and the triple valve pistonchamber, and having passages leading from the train pipe to the pistonchamber and from the check valve chamber to the brake mechanism.

5. In a brake mechanism, the combination with the train pipe the triplevalve and reservoir, ot' a casing containing a valve mechanismarrangedvintermediate of the train pipe and the valve mechanism consisting of apiston held to its extreme throw by a spring and a check valve arrangedin the head of the said piston, the valve held to its seat by a spring,ports leading from the side of the piston to the valve seat, the passagein the casingleading from the train pipe to the piston chamber andthrough the valve chamber to the brake operating mechanism,substantially as described.

6. In an automatic air brake mechanism the combination with the trainpipe, the triple valve and reservoir of the retaining valve mechanismbetween the train pipe and the brake operating mechanism, a triple valvechamber having large ports and the auxiliary mechanism on the triplevalve piston consisting of the loose collar H having edge ports and thespring between the collar and the piston whereby the piston will beactuated by and cover the large cylinder ports when under equalpressure, substantially as described.

-7. In a brake mechanism, the combination with .the triple valve chamberhaving the long and short ports 18 and 15 respectively, of the piston,the triple valve, and the loose collar H, having edge ports 16, thespring S between the collar and the piston, separating them when underequal pressure and thereby closing the shorter ports 15, by the piston,substantially as described.

8. In an automatic air brake system, the

combination with the mechanism described pressure from the triple valvechamber when 10 for filling the brake reservoir quickly, c0nthe pressurein the train pipe is reduced. sisting of a triple valve chamber havinglarge In testimony whereof I affix my signature ports permitting the airto freely pass around in presence of two witnesses.

5 the )iston to the auxiliary reservoir, means V 1 Y V for actuating thepiston by and cover the I SAMLEL HhGn LO FTOM' large ports when thereservoir is filled, of a Witnesses: retaining valve between the triplevalve pis- A. ll. SVVARTHOUT, ton and the train pipe adapted to resistthe S. 'l. ORAPO.

